How late would you issue a landing clearence

[charlie-india-mike]

Quick question?

How late would you leave it to issue a landing clearence to a solo PPL student?

Yesterday, I was down to 100' and about 250 meters from the threashold without getting a landing clearence. There was nothing on the runway and I asked again for clearence to land and got a negitive in reply. This phased me a bit so I decided to initiate a go around.

What should I have done?

[spekesoftly]

Firstly please bear in mind that ATC is not necessarily always aware that a pilot is a solo PPL student. If they are, I would hope and expect their instructions to take account of a pilot's relative inexperience. Without a landing clearance, in the circumstances you descibe, you were quite correct to go around.
Many years ago, I was taught to go around no lower than 250' (QFE), if no landing clearance received. I don't know how universal, or otherwise, this teaching may be.

Have you had a chance to discuss this with your instructor? He, in turn, might be able to speak to the ATC unit concerned, to seek clarification.

[Spitoon]

Yes, you were quite right to go-around if you felt unhappy with continuing the approach.

A landing clearance can be issued at any time before the wheels hit the ground but, of course, it's much better to give the clearance much earlier. If I have to give a late landing clearance I will warn the pilot and, if at all possible, explain why. With this information a pilot is better able to judge when he/she fells it is appropriate to initiate a go-around.

One last though, although you felt that there was nothing on the runway it's sometimes surprisingly difficult to spot something on the runway.

[S76Heavy]

Sometimes ATC used the line "expect late landing clearance due to.." in my student days (and they still do).
The latest clearance I ever got was when I called final, was told "no 1", reported short final, told to "continue, still no 1)
" and I finally exclaimed "extremely short final" as I crossed the threshold and was only then cleared to land.
Fortunately, no performance problems and runway unobstructed in my rollout area, but further down there was another student struggling with his t/o. Interesting..;)